Aerial monitoring

Aerial drones open-up a birds-eye, real-time perspective of our coral reefs that has been unachievable in the past.  

AIMS is applying drones to cost-effectively survey shallow, clear-water reef flats that are inaccessible to divers and vessels, and to assist with in-water platform management from locating underwater buoys quickly to identifying new features for further underwater investigation. Drones are also proving an effective alternative to manned aircraft and satellite surveys during reduced visibility such as low cloud cover. 

Over the past few years, AIMS has invested in about 10 commercial-grade drones with capacity to carry cameras and up to 6kg of sensing equipment to increase marine data collection.  

Collected drone data comes in many forms, from standard high-resolution imagery, to thermal imagery to hyperspectral datasets. These datasets provide a variety of information on the marine environment including water quality, temperature, coral reef health over time and bathymetry maps. 

 

Drones can be deployed from AIMS vessels in the field as a very cost-effective method of aerial survey compared with manned aircraft. Some small field-ready drones are capable of flight times of over 90 minutes, overcoming past limitations of battery capacity. 

AIMS drone capability can routinely capture detailed, high resolution reef surveys at-sea that can identify coral species and health. They are also useful for monitoring areas such as mangroves that may be hazardous for divers due to wildlife or other environmental conditions.  

AIMS drones can collect routine water samples for site environmental monitoring. Another common drone payload used is a hyperspectral camera which provides extensive information on benthos (e.g. coral) in the captured image. Drones also assist in rapidly locating in-field underwater equipment such as submerged oceanographic buoys. 

The drones take off from a launch pad on the ground, a tender (small vessel) or a ship. They can fly to pre-programmed locations or be manually controlled via remote control by the pilot. 

Aerial or coral reef with a zoomed in section
An orthomosaic of Davies Reef, central Great Barrier Reef

AIMS has CASA certification, an on-site Chief Pilot, trained and certified operators, and has completed hundreds of drone flight hours on both the east and west coast of Australia. 

Promising routine marine monitoring applications for drones include:  

  • plume monitoring survey: mapping and tracking plumes such as those from dredging and floods. 

  • algal bloom and oil slick monitoring: mapping and tracking algal blooms and surface slicks such as oil spills, trichodesmium (bacteria also called ‘sea sawdust’) and coral spawning slicks. Different sensors may also enable classification of the slick’s contents by analysing the reflected energy. 

  • benthic monitoring survey: a survey of an inter-tidal or shallow submerged coral reef yields images that can be used for analysis of benthic (seabed) health and biodiversity. 

  • coral bleaching survey: drone could help identify potentially bleached areas for further investigation. 

  • bathymetry mapping: a drone uses structure by motion to estimate depth within its images. Preliminary investigations show the bathymetry maps drones create could be converted into scientifically-valid datasets. 

  • cyclone surveys: when ships are grounded due to natural disasters such as cyclones, drones can conduct damage assessment surveys. 

  • infrastructure inspections: assist authorities conducting safety certifications for AIMS infrastructure in the field, or quickly locating submerged infrastructure such as buoys. 

  • permit compliance: when conducting potentially risky work in the field, AIMS could monitor progress from the air to manage risk and permit requirements. 

  • mission planning: a drone can rapidly survey a reef area to assist scientists to target their underwater surveys. 

  • surveys in rough seas: a drone can fly in rough oceans (when the wind is no more than 10-15 knots), enabling scientists to gather datasets when the weather prevents tenders from accessing required areas. 

  • aerial surveys in cloud cover: satellite imagery surveys are limited in cloudy areas. Drones can conduct benthic surveys under the clouds to support national level broad-scale survey datasets. 

  • water analysis survey: a drone can lower a sensor or device such as a sample bottle to a fixed depth or profile the water column.   

  • ocean colour ground truth: a drone provides a means of measuring ocean colour from a known height. This could be used to validate satellite data or model outputs. 

 

Further information